Strange Flashing when Playing

[Valdarez]

The graphics are flashing when I play. At one point, it even went all black, and I had to kill the program in Task Manager.

The problems seem to be on the hills, as you move up and down it flashes, although I occassionally see the same problem when trees are being knocked down.

My system specifications are below, I have updated to the latest graphics and ATI drivers. Any help would be greatly appreciated.

Mega 865 PC
- Intel P4 3.2 Ghz - Northwood Core
- Western Digital 10k RPM SATA Hard Drive
- HIS ATI Radeon Excalibur 9800 Pro IceQ
- Plextor 708A - 8X DVD Burner
- 1 Gig Kingston 3200 RAM (dual - 2x 512 MB)
- Windows XP Professional - OS

External
- 250 Gig Maxtor One-Touch HardDrive
- 4-Port Belkin USB Hub
- KDS CD Organizer (holds 75 CDs)
- Klipsch 5.1 Speakers
- HP PSC 750 Printer
- Flexiglow Gamer MousePad (USB enabled)
- Belkin Universal Series 800VA UPS